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Dive Com "No Fly Time" Compared?

Dive Com "No Fly Time" Compared?

Post Number:#1  Postby Rol_an_dive » Wed Aug 08, 2007 3:19 pm

I had the opportunity of 3 dives in Bali, buddied with a guy using a Suunto D9, kept close together as currents strong etc., after 3 dives I had 18hrs No Fly, he showed 24hrs, thats a big differrence IMHO, anyone else done comparisons with Dive coms? I dont expect them to be exact, but 18<24 is a big jump. (-I use an Alladin 2G)
Rol_an_dive
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#2  Postby adik » Wed Aug 08, 2007 3:43 pm

What I an say is Suunto is much more conservative than Uwatec.
adik
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#3  Postby kimseng » Wed Aug 08, 2007 3:46 pm

It also depends on the model it uses. I think the D9 uses the RGBM model. Dunno about aladin though.
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Re: Dive Com "No Fly Time" Compared?

Post Number:#4  Postby bijan » Wed Aug 08, 2007 3:54 pm

aladin using buhlman rite?
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Re: Dive Com "No Fly Time" Compared?

Post Number:#5  Postby kimseng » Wed Aug 08, 2007 4:07 pm

My old suunto octopus is using a modified haldane model and it is less conservative than my RGBM based dive com. Since i've got the new one i didn't go back to haldane. I've seen too many friends visit colonel halim in lumut. Ohh come to think of it they were using aladin!
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Re: Dive Com "No Fly Time" Compared?

Post Number:#6  Postby Quero » Wed Aug 08, 2007 4:22 pm

The other thing is, sometimes it's easy to confuse no fly with desat time. Desat time is always a *lot* longer, yielding results like what you saw. My first reaction was that it might be that, but the different algorithm models mentioned are also a good possibility (Buhlmann vs RGBM), and I was glad to see that kimseng brought it up.

Uwatec is more conservative in some ways and less in others. Suunto uses algorithms that allow less bottom time and penalize more on N2 uptake. Uwatec is less conservative on bottom time but is hell on ascents! Suuntos let you ascend a huge amount faster than Uwatec. Personally, since I'm not often very close to my NDL, I'd rather have a slower ascent forced on me.
Quero
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#7  Postby Rol_an_dive » Wed Aug 08, 2007 4:27 pm

the blurb says "Bühlmann ZH-L8 ADT MB PMG (Adaptive Microbubble Predictive Multi-Gas)" and it also allows you to choose the micro-bubble level to suit yourself. I had thought that the Aladdin was conservative, but I will start to do comparisons to check it out, I have had no 'bentness' yet using it, but want to stay ahead of that game!
Rol_an_dive
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#8  Postby Rol_an_dive » Wed Aug 08, 2007 4:34 pm

The other thing is, sometimes it's easy to confuse no fly with desat time. Desat time is always a *lot* longer, yielding results like what you saw. My first reaction was that it might be that, but the different algorithm models mentioned are also a good possibility (Buhlmann vs RGBM), and I was glad to see that kimseng brought it up.

Uwatec is more conservative in some ways and less in others. Suunto uses algorithms that allow less bottom time and penalize more on N2 uptake. Uwatec is less conservative on bottom time but is hell on ascents! Suuntos let you ascend a huge amount faster than Uwatec. Personally, since I'm not often very close to my NDL, I'd rather have a slower ascent forced on me


That would explain my challenge in Redang late June, dived with Nizam and had to do 2 deco stops to his one, ended up SOS and no dive allowed as I cut the final 5m/ short. bottom time was excessive though, for the third time that day.... ::)
Rol_an_dive
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#9  Postby bubble » Wed Aug 08, 2007 10:26 pm

I had the opportunity of 3 dives in Bali, buddied with a guy using a Suunto D9, kept close together as currents strong etc., after 3 dives I had 18hrs No Fly, he showed 24hrs, thats a big differrence IMHO, anyone else done comparisons with Dive coms? I dont expect them to be exact, but 18<24 is a big jump. (-I use an Alladin 2G)



So what is your decision?
follow dive comp -fly after 18 hours or follow 24 hours?
bubble
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#10  Postby Ozfish » Wed Aug 08, 2007 10:34 pm

D9 sucks...mine just kaput halfway thru a dive with no reason sofware hang...sending to suunto for autopsy....sheeshh...gotta go bck to ma all time fav Aladdin
Ozfish
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#11  Postby anas » Wed Aug 08, 2007 10:44 pm

According to D9 manual, it's always at least a 12-hr No Fly or equiv to desaturation time (if desat time is longer than 12hrs).

For desat times lower than 70mins, there will be no No-Fly time.

DAN recommends a min 12 hrs SI  in order to fly up to 2.4km alt.
UHMS recommends 24hrs.
But Suunto recommends both DAN and UHMS to be satisfied before you can fly, hence D9 shows 24hrs.

That's what the manual says.
Cheers!
Last edited by sheik on Thu Aug 09, 2007 5:59 am, edited 1 time in total.
anas
 
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Re: Dive Com "No Fly Time" Compared?

Post Number:#12  Postby jgshuwei » Wed Aug 08, 2007 10:55 pm

I have no theory to back me up, anything more than 18 hrs after multiple dives is good. If I can stay longer than that before take-off, even better.
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Re: Dive Com "No Fly Time" Compared?

Post Number:#13  Postby zani » Thu Aug 09, 2007 2:19 pm

jgshuwei wrote:I have no theory to back me up, anything more than 18 hrs after multiple dives is good. If I can stay longer than that before take-off, even better.


Me too, i'll follow what's apeared on the comp and  can stay longer as i can.
.....let's get wet and blow some bubbles.......!!!
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Re: Dive Com "No Fly Time" Compared?

Post Number:#14  Postby kimseng the maverick rogue » Thu Aug 09, 2007 2:47 pm

it's always safer to stay on the ground longer... i always make it a point to wait 24h before flying.
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add the bed, substract the clothes, divide the legs & pray U don't multiply...
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Re: Dive Com "No Fly Time" Compared?

Post Number:#15  Postby John F SeaDemon » Thu Aug 09, 2007 9:09 pm

That is why although I have a dive comp, I'll plan my dives using me RDP, and my no-fly time is always 24-hours after end of last dive. Electronics, for me, don't mix well with water
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